Development of Ruby Laser System for Medical Use

Abstract

We have developed new Ruby laser system (TMRL series) for the treatment of hyperpigmented skin lesions, such as pigmented nevus (melanin particle deposition), tattoos and so on. The prototype of this series invented in 1980 included a lens-type applicator, which was attached to the oscillator. In 1981 we developed a kaleidoscope (quartz square pillar), which enables us to obtain a homogenous output energy distribution. In addition, it provides a square area of irradiation. So, we can perform efficient treatment. In 1982 we also succeeded in developing a fiber optic induced system using quartz fibers, first in the world. The fiber manipulator and the handpiece separated from the oscillator assure us of much better handiness. After that we have improved the power supply into a smaller and lighter one and adopted a shorter irradiation interval. In 1987 we commenced delivery of commercial units, model LRT-301A, after obtaining the approval for its manufacture and clinical application from the Ministry of Health and Welfare of Japan. This equipment is characterized by the output energy of 20-40J/cm², pulse width of 2 msec, irradiation interval of 10 sec, irradiated area of 10×10 and 15×15mm, and electrical input of 100V (single phase), 30A, 50/60Hz. We can obtain far better results by ruby laser treatment than by the conventional methods, though we realized its limitation. We are now developing a shorter pulse width in expectation of better selective effects of laser treatment.